Musical instruments



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MUSICAL INSTRUMENTS Filed Feb. 5, 1963 5 Sheets-Sheet 5 INVENTORS: JAMESOR MSYON 8114' N s Sec 0 ON SPENCEQ Can u nuaf United States Patent3,196,729 MUl CAL HIQSTRUMENTS llamas @rmston Burns, Buclrhurst Hill,and Gordon Spencer Qhandler, Frimley, near Aldershot, England, assignorsto Ormston Burns Limited, London, England Filed Feb. 5, 1963, Ser. No.256,363 Claims priority, application Great Britain, Feb. 5, ,1962,

is (Ilaiins. Yet. 84-171} The present invention relates to musicalinstruments and is more particularly concerned with stringed instrumentsespecially those having a fretted finger board such as guitars.

The utility of a guitar as a solo instrument or in combination withother instruments is well known, and at the present time there isconsiderable demand for an electric guitar which customarily has a solidbody carrying one or more pick-up units for deriving electrical signalsfrom vibrations of the strings which are usually of metal, the signalsfrom the pick-up units being applied to one or more amplifier andloudspeaker systems for the production of audible sounds.

The present invention envisages utilizing the strings and finger boardas a selector switch for controlling the operation of one or more othermusical instruments or sound-producing devices.

Thus according to one feature of the present invention a stringedmusical instrument, such as a guitar, includes switching means adaptedfor selective operation upon the fiigering of one or more strings on thefinger board for controlling the operation of at least one othersound-producing device.

The switch means may be in the form of a plurality of switches havingnormally open contacts and each responsive to pressure applied to aparticular fret when a particular string is stopped against the fingerboard adjacent thereto, or to the application of digital pressure to aparticular string against a particular locality of the finger board.Either of such arrangements can be used with either metallic ornon-metallic strings, and moreover, the latter of such said arrangementscan be utilized in a stringed instrument provided with a fingerboardhaving a continuous outer surface, that is to say a fingerboard on whichno frets are provided.

in a preferred arrangement, however, it is envisaged providing th fretswith metal string-engaging portions and providing metal strings, so thateach string and each of the frets with which it may come in contactserve as switching contacts.

in a multiple-stringed instrument it is necessary that each of thestrings should be electrically insulated from the other strings, andthis may readily be achieved either by providing the instrument with abridge of non-conducting material or a bridge havin metallicstringengaging portions electrically insulated from one another, byanchoring the ends of the strings below the bridge either in ananchorage or in a tromulant device in such a manner that they areinsulated from one another, and by electrically insulating from oneanother the spindles of the winding mechanisms for the strings at themachine head.

in order to avoid cross-feed from one st in to another, it is desirablethat each fret in the finger boards should include a number of metallicstring-engaging portions equal to the number of strings, the individualmetallic string-engaging portions in each fret being insulatedelectrically from one another. For example, a fret may be in the form ofa moulded base of a plastic material such as nylon and having at oneedge a slot or groove to receive, at spaced intervals from one another,a series of metallic inserts of good electrically conducting materialsuch as silver or nickel-silver to serve as string engaging portions.The separation between adjacent inserts in a fret base moulding can bemaintained by the insertion of insulators therebetween. Such aconstruction has the advanta e that it is possible to replace thestring-engaging inserts without necessitating the replacement of thefret base moulding. Electrical connections to the string-enportions ofthe frets may conveniently be made by means of a printed circuit boardinterposed between the neck of the instrument and the finger board. Suchprinted circuit boards may be provided with miniature pin sockets toreceive miniature pins projecting from the fret base moulmngs andconnecting with the metallic inserts therein.

in another envisaged construction, each fret comprises a plurality offret segments, each formed such as by casting in a suitable electricallyconducting material such as nickel silver and each having, at one end, aminiature pin for insertion in a miniature socket in the printed circuitboard. To form a complete fret, the approprate number, for example fouror six, fret segments are compression moulded in, for example, aphenolic resin, to form a unit wherein the segments are spaced from oneanother and insulated from one another.

t suitable bridge can be constructed in a somewhat r manner to a fretand can comprise a base moulding of a plastic material such as nylon andhaving at its upper edge a groove to receive a plurality of metalinserts in spaced relationship to one another. Whilst a bridgeconstructed entirely of insulating material could be used, it ispreferable for metallic string-engaging elements to be provided and animprovement in the tone and in the decay tim of oscillation of a stringcan be obtained by tensioning a string at a location as near aspractical behind the bridge. For this purpose the bridge may be providedwith a plurality of apertured plate units disposed at spaced a littlefrom the side thereof remote from the finger board and having theirapertures at localities nearer to the base of the bridge than itsassociated stringengaging metal inserts.

The ends of the strings behind the bridge may be anchored in aconventional anchoring plate and insulated therefrom and from oneanother by providing inserts of an insulating material in the normalstring-receiving bores of the anchoring plate. Alternatively the ends ofthe strings may be anchored in a tremulant unit. Such a trernulant unitis often provided with a metal spindle having a series of diametralbores therethrough, each string passing around a portion of the outerperiphery of the spindle and then through a bore and being anchored bybeing wound around toggle element and twisted around itself. With such atremulant unit the strings can conveniently be insulated from oneanother by providing the spindle with an external sheath of aninsulating material such as nylon and by lining each of the bores with asleeve of insulating material such as nylon and having at one end arecess to receive a toggle element. Electrical connections to thestrings may convenientl be made by leads connecting with the metalstring-engaging inserts on the bridge.

In a simple embodiment, the stringed instrument has a single metallicstring, or if mul-ti-stringed, has a single metallic string, the othersbeing non-metallic. Electrical connection is made to the metallic stringand to each of the frets, so that signals can be derived correspondingto the fingering of that string. In such an arrangement it is notnecessary for the frets to have a segmented construction and thus eachfret can be a suitably shaped piece of metal. In an instrument providedconveniently with twenty-four frets, the single string in combinationwith the frets can serve as a twenty-four way selector switch. Signalsderived therefrom may be used to control any other musical instrumentcapable of being ops ea /as erated by remote control or may be used tocontrol an electronic sound-producing device. The signals produced maythus be applied to part of the control circuitry of an organ havingelectric or electro-pneumatic action, or may be applied to a series ofdevices for operating a Vibraphone or a Xylophone, or yet again beapplied to control the pitch or frequency of an electric oscillatorycircuit system connected to an amplifier and loudspeaker system so thataudible sounds having a fundamental pitch corresponding to thefundamental or a harmonic or a sub-harmonic of the note for which thestring is fingered can be produced independently of vibration of thestring. Since, under conditions where a string is not fingered, i.e.where the string is used as an open string, the'st-ring would normallymake contact with the fret nearest the machine head, auxiliary switchmeans may be provided in series with that fret to obivate the continuousproduction of a sound at a pitch corresponding thereto when theinstrument is not being played or fingered. Such auxiliary switch mayconveniently be in the form of a foot switch.

It will of course be understood that signals derived from any or all ofthe pick-up units in response to vibration of the string or strings canalso be applied to an amplifier and loudspeaker system in a conventionalmanner so that many combinations of sounds of differing tone, timbre andquality can be obtained.

By employing more strings and providing metal stringengaging segments onthe frets a greater number of switch signals can be derived; forexample, with a six-stringed guitar provided with twenty-four frets, amaximum of six times twenty-four switches is available. Although in mostcases such individual switches will be operated in chord combinations ofsix in dependence on the fingering of individual strings, in order tomake full use of all such switches an external multi-core lead having anumber of cores at least equal to the number of strings multiplied byone more than the number of frets, for example six multiplied bytwenty-five which is equal to one hundred and fifty in the exampleselected, is required.

The switches formed by the fret segments and the strings can be utilizedin low voltage control circuits or for direct switching or may beutilized to control a bank of relays having contacts which can beconnected in any desired manner to control other apparatus. In oneembodiment it is envisaged that additional sound-producing apparatus maytake the form of a number of variable frequency oscillators, eachassociated with an individual string and that the switches provided bythat string and its associated fret segments be embodied in a frequencycontrol circuit.

There is at the present time some demand for a vibraphone in combinationwith a guitar and the present invent-ion envisages that the switchingnetwork may be employed for controlling percussive operating mechanismfor a Vibraphone.

The invention will be further described by way of example with referenceto the accompanying drawings, in which:

FIGS. 1A and 1B are block schematic diagrams showing a guitar providedwith a selector switch means responsive to fingering of the strings onthe finger board for controlling another sound-producing device ordevices,

FIG. 2 is a section along the line lIlI of FIG. 3 and is a detail viewof the neck and finger board according to one embodiment in which fretsegments are movable and have an individual switch associated therewith,

FIG. 3 is a section along the line Ill-4H of FIG. 2,

FIG. 4 is a section along the line IV-IV of FIG. 5 and is a detail viewof the neck and finger board according to another embodiment in whichfinger board parts are movable and have individual switches associatedwith them,

FIG. 5 is a section along the line VV of FIG. 4,

FIG. 6 is a section along the line Vii-VI of FIG. 7 and is a detail viewof the neck and finger boards according to another embodiment in whichfrets have metal string engaging covers,

FIG. 7 is a section along the line VIlVil of FIG. 6,

FIG. 8 is a section along the line VIII-Vll1 of FIG. 9 and is a detailview of the neck and finger board according to a further embodimentincluding a printed circuit board for connecting with the fret segments,

FIG. 9 is a section along the line IXIX of FIG. 8,

FIG. 10 is a detail section to an enlarged scale of one form of fret,

FlG. 11 is a transverse section of another form of fret in which fretsegments are moulded into a unit,

PEG. 12 is a perspective view of one form of bridge,

FIG. 13 is a transverse section of the bridge shown in FIG. 12,

FIG. 14 is a perspective view of one form of tremulant unit in which thestrings can be insulated from one another,

FIG. 15 is a detail sectional view of the spindle of the tremulant unitshown in FIG. 14,

FIG. 16 is a sectional view of a combined bridge and tremulant unit inwhich the strings can be insulated from one another,

FIG. 17 is a block diagram of one arrangement in which an oscillator isassociated with each string of a guitar and in which external connectionis made with each string and fret segment.

Referring initially to FIG. 1, a guitar 3!} comprises a body 31, a neck32 having a finger board 33 and a ma chine head 34, a bridge 35, atremulant unit 36, strings 38, and pick-up units 37. In a conventionalconstruction the body 3 1 of an electric guitar is solid, and up to foursets of pick-up units 37 are provided, Signals from the pick-up units,selected and mixed at 41 as desired, are fed to an amplifier as andloudspeaker 49 for producing sounds derived from the vibrations of thestrings.

A guitar according to the present invention is provided with a pluralityof switching means indicated generally at 42 each associated with aparticular string and a particular fret on the finger board. Theswitching means may be in the form of small switches located below thefinger board and mechanically operated either by movable portions orsegments of the frets upon application of pressure thereto by a stringor by movable portions of the finger board itself upon application ofdigital pressure thereto through a string, as will be hereinafterdescribed. A multi-core lead 43 connects the switching means to controlthe operation of one or more other sound-producing devices orinstruments such as a Variable frequency oscillatory system it feedingan amplifier 45 and loudspeaker 46. The system 44 may be a singleoscillator or a plurality of oscillators and produce either a singlenote which corresponds to the highest or the lowest note fingered on thestrings on the finger board, or a chord combination corresponding to allthe notes fingered on all the strings, some or all of the notes beingpassed additionally or alternatively to a second amplifier 47 andloudspeaker A switching network 4-9 such as a relay bank, may beinterposed between the switching means 42 and any devices controlledthereby and arranged to provide signals in a form acceptable to thecontrol system of any other electrically operated or controlled musicalinstrument such as an organ having electric or electropneurnatic actionor a Vibraphone. A lead 50 can extend from the switching network 49 to acontrol relay bank 511 between a console 52 and organ chamber 53.Fingering the finger board 33 of the guitar can effectively beequivalent to playing upon one or more manuals of the organ which may beblown and have pipes or may be electric or electronic. A lead 54 can beextended from the switching network 49 to a striking mechanism 55 foroperating a Vibraphone 56.

in another arrangement the frets of the finger board are provided withmetal string-engaging portions and these in combination with metalstrings serve as the switches of the switching means. A multicore lead57 connects the strings to the oscillatory system 44 directly or throughthe switching network 49.

One arrangement of a guitar neck in which SV/liC1- are provided isillustrated in FIGS. 2 and 3. Each fret 6d comprises a plurality of fretsegments such as til-one for each string, slidably mounted in the fingerboard 33. Between the finger board and the neck is a set of smallswitches, one for each fret segment, such as switch 62 for the segment61. When digital pressure is applied to a string adjacent a. selectedfret, pressure of the string on the fret segment concerned displaces thefret segment and operates the switch associated therewith.

Another arrangement is illustrated in FIGS. 4 and 5. Adjacent each fretso the finger board is provided with a plurality of small displaceablesections such as 65, the number of sections being equal to the number ofstrings. Below each section is a small switch, such as 64 which isassociated with the section 63. When digital pressure is applied to astring adjacent a selected fret, pressure is also applied to therelevant section which is thereby displaced and effects actuation of theassociated switch.

Arrangements of the neck and finger board in which metal string engagingportions are provided are illustrated in FiGS. 6 and 7, 8 and 9, 10, and11. In the construction shown in FIGS. 6 and 7 each fret do is providedwith a plurality of metal string engaging segments 65 of good electricalconductivity and with easy solderability. Silver and nickel-silver aresuitable examples. The segments may be electro-deposited, or in the formof films or thin sheets adhesively secured or moulded onto a base 66 ofinsulating material such as nylon. Connection is made to the segments bysoldered leads, such as lead 67 soldered to the segment 65. When it isdesired to replace a fret in the course of normal wear and tear it isnecessary to unsolder the connections,'remove the existing fret, inserta fresh fret and solder the connections to the segments of the new fret.This is time consuming and involves the risk that connections may not besoldered to the correct segments. These difficulties can be obviated inthe construction illustrated in FIGS. 8 and 9, or 10, or 11. A printedcircuit board 63 is interposed between the neck .32 and the finger board33 and for each fret is provided with a number of miniature pin sockets69 equal to the number of strings 37. A fret so is provided with anequal number of moulded-in pins 7% which connect with metal stringengaging segments and are receivable in the sockets To facilitate thereplacement of the string enga ing segments 65 a fret can be constructedas illustrated in FIG. 10 with a base moulding 6d of an insulatingmaterial such as nylon embodying the requisite number of spaced pins 7tAt its outer edge the base has a dovetail groove 71 into which the pinsproject slightly: Wire-like se ments '72 can be slid into the grooves 71to project slightly thereabove and at the same time engage theappropriate pin 75} whilst the segments 72 can be separated from oneanother by inserting insulators between adjacent segments. The basemoulding 66 can be provided with a barbed projection "73 which canextend substantially throughout its length or be in the form of a seriesof rod-like sleeves enclosing parts of the pins to assist in retainingthe fret in the fingerboard. In the construction illustrated in FIG. 11the string engaging segments 7 are constructed integrally with the pinslit and the requisite number of segments are assembled togcther into acomposite moulding '75 such as of a phenolic resin or nylon.

When the strings themselves form part of the switches of the switchingmeans in the guitar, it is necessary for the strings to be insulatedfrom one another electrically and for connection to be made to each ofthem. Connection can be most conveniently made at the bridge. One formof bridge 35 is illustrated in FIGS. 12 and 13 and comprises a basemoulding 76 of an insulating material having at its upper edge a numberof metal string engaging portions '77 equal to the number of strings.The portions '77 are of good electrically conducting material to whichconnections can readily be soldered, such as silver or nickel-silver,and are preferably notched for string location purposes. Connectionssuch as 78 are soldered to the portions 77.

Whilst the ends of the strings can be anchored in a conventionalanchorage provided that they are insulated from one another, it ispreferable for them to be anchored in a tremulant unit 36. One form ofsuch unit is illustrated in FIG. 14 and comprises a spindle 79journalled in bearings 8h, 81 carried on a base plate 82 which can besecured directly to the guitar body 31 or can be attached thereto by aflap 33 extending over the bottom edge of the body and secured to thebottom thereof. The spindle 79 may be of an insulating material but ispreferably of metal and is provided with an outer sleevetlike coating 35of an insulating material. Transverse bores as for receiving the stringsare each lined with sleeves lid of insulating material, A string endpasses around part of the periphery of the coated s indle 79, through asleeve and is Wrapped around a toggle element 37 as illustrated in FIG.15. Spring 10% exerts on the spindle "/9 a torque to balance the torqueexerted on the spindle by the strings 38 when tensioned and the spindlecan be angularly displaced manually by handle till.

The bri go and tremulant unit can be combined together into a singlecomposite unit as illustrated in PEG. 16. The spindle 7% is journalledin side members 38 of which only one is shown and a carriage 89 isslidably mounted on rollers hi9, 91, between the side members. Thecarriage as carrie for each string a bridge member 92 which isadjustable in position thereon in a longitudinal direction by means ofan adiustment screw 93 and spring 94, and in an up-and-down direction bymeans of a pair of screws of which one K? is shown. Each bridge memberhas a metal string engaging portion 96 insulated from the rest of thecomposite unit; this is conveniently achieved by constructing eachbridge member of an insulating material such as nylon. Secured to eachbridge member and located on the tremulant spindle side thereof is anapertured plate 9'7 having an aperture 93 through which a string 37passes, the apertured plate causing the string to be bent over thestring engaging portion of the bridge unit at an angle greater than ifit were to pass from the bridge unit directly to the spindle '79 orunder a grooved roller 9% of insulating material or of metal and coatedwith an insulating material such as nylon. Spring 1% xerts in thespindle '79 a torque to balance the torque exerted on it by the strings33 when tensioned and the spindle can be angularly displaced manually bya handle in.

FIG. 17 illustrates in block form an arrangement including sixoscillators 112, i 13, lid, lilo", lilo, 117, each associated one witheach of the strings of a six stringed guitar. Connections to the stringen aging portions of the bricge and to all the string engag g segmentsof the frets are extended to a frequency control system by a rnulticorelead 119 having a number of cores equal to the number of strings 37multiplied by the number of frets The switches formed by the fretsegments associated with any one string and that string cause thefrequency control system 113 to select the frequency of the oscillatorassociated with that string in accordance with the fingering on thefinger board an signals from all the oscillators are passed to a mixer12d and thence to an amplifier i231 and loudspeaker 2122.

We claim:

1. A stringed musical instrument comprising a fingerboard, a pluralityof metallic strings extending over said fingerboard and normally spacedtherefrom, a plurality of spaced transversely extending frets along saidfingerboard, eaci a base moulded or" a plastic rret cor 7 material andhaving at its outer edge a groove, a plurality of metall'c insertsreceived in said groove in spaced relationship to one another, thenumber of inserts in each fret corresponding to the number of stringsand corresponding inserts in all the frets being associated with anindividual string, the application of d ital pressure to any particularstring at a region above a fret bringing that string into engagementwith the associated insert on that fret, means for electricallyinsulating said strings from one another, electrical connecting meansconnected with each of said strings and electrical connecting deansextending through the frets and connected with each of saidstring-engaging inserts, said strings and said stringengaging insertsserving as switching means for controlling the operation of at least oneother sound-producing device.

2. A stringed musical instrument comprising a fingerboard, a pluralityof metallic strings extending over said fingerboard and normally spacedtherefrom, a plurality of spaced transversely extending frets along saidfingerboard, each fret comprising a base moulded in a plastic materialand having at its outer edge a groove, a plurality of metallic insertsreceived in said groove in spaced relationship with one another, thenumber of inserts corresponding to the number of strings andcorresponding inserts in all said frets being associated with anindividual string, the application of digital pressure to any particularstring at a region above a fret bringing that string into engagementwith the associated insert on that fret, and a plurality of spaced pinsmoulded into said base, one end of each pin extending into said grooveto engage electrically with one of said inserts and the other endprojecting from said base, means for electrically insulating saidstrings from one another, electrical connecting means connected witheach of said strings individually and with the other ends of each ofsaid pins individually, said strings and said string-engaging portionsserving as switching means for controlling the operation of at least oneother sound-producing device.

3. A stringed musical instrument comprising a neck, a fingerboard onsaid neck, a plurality of metallic strings extending over saidfingerboard and normally spaced therefrom, a plurality of spacedtransversely extending frets along said fingerboard, each fret having aplurality of electrically conducting string-engaging portions associatedone with each string and a plurality of pins each connected electricallywith an individual string-engaging portion and having one end projectingfrom said fret below said fingerboard, means for electrically insulatingsaid strings from one another, electrical connecting means connectedwith each of said strings individually, and electrical connecting meansconnected with each of said string engaging portions, saidlast-mentioned connecting means comprising a printed circuit board insaid neck adjacent said fingerboard and a plurality of sockets in saidboard for receiving ends of said pins for connecting with saidstring-engaging portions individually, said strings and saidstring-engaging portions serving as switching means for controlling theoperation of at least one other sound-producing device,

4. A stringed musical instrument comprising a neck, a fingerboard onsaid neck, a plurality of metallic strings extending over saidfingerboard and normally spaced therefrom, a plurality of spacedtransversely extending frets along said fingerboard, each fretcomprising a plurality of fret segments assembled in spaced relationshipto one another in a plastic moulding to form a composite unit, eachsegment being generally T-shaped including a bar serving asstringengaging portion and a shank projecting from said moulding toextend below said fingerboard and forming a connecting pin, means forelectrically insulating said strings from one another, electricalconnecting means connected with each of said strings individually,electrical connecting means connected with each of said string engagingportion, said last-mentioned connecting means comprising a printedcircuit board in neck adjacent said fingerboard and a plurality ofsockets on said board for receiving said connecting pins to makeelectrical connection with each of engaging portions individually, saidstrings and said string-engaging portions serving as switching means forcontrolling the operation of at least one other soundproducing device.

5. A stringed musical instrument such as a guitar comprising a body, aneck connected to said body, a fingerboard on said neck, a machine headon said neck, a cor bridge and trernulant device on said body, saidmachine head and said device being adapted to receive a plurality ofmetallic strings extending over said fingerboard in normal spacedrelationship thereto, a plurality of spaced transversely extending fretsalong said fingerboard, each fret having a plurality of electricallyconducing stringengaging portions for association one with each string,said device including a spindle, means for journalling said spindle, anouter coating of insulating material on said spindle, said spindlehaving a plurality of stringreceiving bores, one for each string, alining of insulating material within each bore, spring means forexerting a torque on said spindle, a handle for manually angularlydisplacing said spindle, a plurality of bridge members, one for eachstring, each bridge rncm er being of insulating material and each havinga metal string-engaging portion, means for mounting all of said bridgemembers for longitudinal movement upon variation of tension in stringsupon angular displacement of said spindle, electrical connecting meansconnected with the metal string-engaging portion of the bridge membersindividually, and electrical connecting means extending through saidfrets and connected with the metal string-engaging portions of saidfrets individually, the strings and string-engaging portions of thefrets being adapted to serve as switching means for controlling theoperation of at least one other sound-producing device.

6. An instrument according to claim 5' in which said othersound-producing device comprises an electric oscillatory circuit systemand amplifier and loudspeaker system, said switching means controllingthe pitch or frequency of said oscillatory circuit system.

7. An instrument according to claim 5 in which said othersound-producing device comprises a plurality of variable frequencyoscillators, each associated with an individual string and in which saidswitching means provided by each string and its associated fretstring-engaging portions are embodied in a frequency control circuit forthe oscillator associated with that string.

8.'An instrument according to claim 5 in which said othersound-producing device is a Vibraphone and in which said switching meansis applied through a switching network to control percussive operatingmechanism for such Vibraphone.

An instrument according to claim 5 in which said other sound-producingdevice is an organ having electric or electropneumatic action and inwhich said switching means is adapted to control a said organ through aswitching network.

lltl. An instrument according to claim 5 including at least one pick-upfor deriving electrical signals from vibrations of the strings andfeeding signals to an amplifier and loudspeaker system.

Jill. A stringed musical instrument such as a guitar comprising a body,a neck connected to said body, a fingerboard on said neck, a machinehead on said neck, a combined bridge and tremulant device on said body,said machane head and said device being adapted to receive a pluralityof metallic strings extending over said fingerboard in normal spacedrelationship thereto, a plurality of spaced transversely extending fretsalong said fingerboard, each fret having a plurality of electricallyconducting string-engaging portions for association one with eachstring, said device including a spindle, means for journalling saidspindle, an outer coating of insulating material ti on said spindle,said spindle having a plurality of stringreceiving bores, one for eachstring, a lining of insulating material Within each bore, spring meansfor exerting a torque on said spindle, a handle for manually angularlydisplacing said spindle, a plurality of bridge members, one for eachstring, each bridge member being of insulating material and each havinga metal string-engaging portion, means for mountin all of said bridgemembers for longitudinal movement upon variation of tension in stringsupon angular displacement of said spindle, electrical connecting meansconnected with the metal string-engaging portions of the bridge membersindividually, and electrical connecting means connected with each ofsaid string engaging portions, said last-mentioned connecting meanscomprising a printed circuit board in said neck adjacent saidfingerboard and pin-like connections extending from said printed circuitboard through said frets and connect- With the metal string-engagingportions of said frets individually, the strings and string-engagingportions of the frets being adapted to serve as switching means forcontrolling the operation of at least one other sound-producing device.

12. A stringed musical instrument such as a guitar comprising a body, aneck connected to said body, a fingerboard on said neck, a machine headon said neck, a combined bridge and tremulant device on said body, saidmachine head and said device being adapted to receive a plurality ofmetallic strings extending over said fingerboard in normal spacedrelationship thereto, a plurality of spaced transversely extending fretsalong said fingerboard, each fret comprising a base moulded of a plasticmaterial having at its outer edge a groove, a plurality of metallicinserts received in said groove in spaced relationship to one another,the of inserts in each i'ret corresponding to the number of strings andcorresponding inserts in all the frets being associated with anindividual string, said device including a spindle, means of journallingsaid s indie, an outer coating of insulating material on said spindle,said spindle having a plurality of st ing-receiving bores, one for eachstring, a lining of insul ating material with each bore, sp ing meansfor exerting a torque on said spindle, a handle for manually angularlydisplacing said spindle, a plurality of bridge members, one for eachstring, each bridge member being of insulating material and each havinga metal string engaging portion, means for mounting all of said bridgemembers for longitudinal movement upon variation of tension in stringsupon angular displacement of said spindle, trical connecting meansconnected with the metal stringengaging portions of the bridge membersindividually, and electrical connecting means extending through saidfrets and connected W' h the metal stringengaging portions of said fretsindividually, the strings and string-engaging portions of t e fretsbeing adapted to serve as switching means for controlling the operationof at least one other sound-producing device.

A stringed musical instrument such as a guitar comprising a body, a neckconnected to said body, a fingerboard on said neck, a machine head onsaid neck, a combined bridge and tremulant device on said body, saidmachine head and said device being adapted to receive a plurality ofmetallic strings extending over said lingerboard in normal spaced relaionship thereto, a plurality f spaced transversely extending frets alongsaid lingerboard, each fret comprising a base moulded in a plasticmaterial and having at its outer edge a groove, a plurality of metallicinserts received in said groove in spaced relationship with one another,the number of inserts corresponding to the number of strings andcorresponding inserts in all said frets being associated with anindividual string, the application of digital pressure to any particularstring at a region above a fret bringing that string into engagementwith the associated insert on that fret, and a plurality of spaced pinsmoulded into said base, one end of each pin extending into said grooveto engage electrically With one of said inserts and the other endprojecting from said base, said device including a spindle, means forjournalling said spindle, an outer coating of insulating material onsaid spindle, said spindle having a plurality of string-receiving bores,one for each string, a lining of insulating material Within each bore,spring means for exerting a torque on said spindle, a handle formanually angularly displacing said spindle, a plurality of bridgemembers, one for each string, each bridge member being of insulatingmaterial and each having a metal stringengaging portion, means formounting all of said bridge members for longitudinal movement uponvariation of tension in strings upon angular displacement of saidspindle, electrical connecting means connected With the metalstring-engaging portions of the bridge members individually, andelectrical connecting means connected With each of said string-engagingportions, said last-mentioned connecting means comprising a printedcircuit board in said neck adjacent said fingerboard and a plurality ofsockets in said board for receiving the said projecting ends of saidpins for connecting With said stringengaging portions individually, thestrings and stringengaging portion of the frets being adapted to serveas switching means for controlling the operation of at least one othersound-producing device.

14. A stringed musical instrument such as a guitar comprising a body, aneck connected to said body, a fingerboard on said neck, a machine headon said neck, a combined bridge and tremulant device on said body, saidmachine bead and said device being adapted to receive a plurality ofmetallic strings extending over said fingerboard in normal spacedrelationship thereto, a plurality of spaced transversely extending fretsalong said fingerboard, each tret comprising a plurality of fretsegments ssernbled in spaced relationship to one another in a plasticmoulding to form a composite unit, each segment being generally T-shapdincluding a bar serving as string-engaging portion and a shankprojecting from said moulding to extend below said fingerboard andforming a connecting pin, said device includin a spindle, means forjournalling said spindle, an outer coating of insulating material onsaid spindle, said spindle having a plurality of stringreceiving bores,one for each string, a lining of insulating material Within each bore,spring means for exerting a torque on said spindle, a handle formanually angularly displacing said spindle, a plurality of bridgemembers, one for each string, each bridge member being of insulatingmaterial and each having a metal string-engaging portion, means formounting all of said bridge members for longitudinal movement uponvariation of tension in strings upon angular displacement of saidspindle, electrical con necting means connected With the metalstring-engaging portions of the bridge members individually, andelectrical connecting naeans connected with each or": saidstring-engaging portions, said last -mentioned connecting meanscomprising a printed circuit board in said neck adjacent saidfingerboard and a plurality of sockets in said board for receiving endsof said pins for connecting with said string-engaging portionsindividually, the strings and string-engaging portions of the fretsbeing adapted to serve as switching means for controlling the operationof at least one other sound-producing device.

l5. A stringed musical instrument comprising a body, a tremulant deviceon said body, a neck connected to said body, a bridge on said body, afingerboard on said neck, a machine cad on said neck, said instrumentbeing adapted to receive a plurality of metallic strings extending fromsaid machine head over said fingerboard in normal spaced relationshiptherefrom, over said bridge to said tremulant device, a plurality ofspaced transversely extending frets along said fingerboard, each frethaving a plurality of electrically conducting string-engaging portionsassociated one With each string, said bridge having 1 l a plurality ofelectrically conducting stringengaging portions each for engagement byan individual one of said strings, electrical connecting means connectedWith each of said string-engaging portions of said bridge individually,electrical connecting means extending through the frets and connectingWith each of said string-engaging portions individually, said deviceincluding a spindle, means for journalling said spindle, an outercoating of insulating material on said spindle, said spindle having aplurality of string-receiving bores, one for each string, a lining ofinsulating material Within each bore, spring means for exerting a torqueon said spindle, a handle for manually angularly displacing saidspindle, said strings and said string-engaging portions of said fretsbeing adapted to 12 serve as switching means for controlling theoperation of at least one other soundproducing device.

References Cited lay the Examiner UNITED ST1- TIES PATENTS 496,358 1/93Montanelli 84-171 1,384,843 7/21 Maxwell 84-171 2,912,894 11/59 Hess84-471 FOREIGN PATENTS 562,119 7/30 Germany.

LEYLAND M. MARTIN, Primary Examiner.

LEO SlvfiLOW, Examiner.

1. A STRINGED MUSICAL INSTRUMENT COMPRISING A FINGERBOARD A PLURALITY OFMETALLIC STRING EXTENDING OVER SAID FINGERBOARD AND NORMALLY SPACEDTHEREFROM, A PLURALITY OF SPACED TRANSVERSELY EXTENDING FRETS ALONG SAIDFINGERBOARD, EACH FRET COMPRISING A BASE MOULDED OF PLASTIC MATERIAL ANDHAVING AT ITS OUTER EDGE A GROOVE, A PLURALITY OF METALLIC INSERTSRECEIVED IN SAID GROOVE IN SPACED RELATIONSHIP TO ONE ANOTHER, THENUMBER OF INSERTS IN EACH FRET CORRESPONDING TO THE NUMBER OF STRINGSAND CORRESPONDING INSERTS IN ALL THE FRETS BEING ASSOCIATED WITH ANINDIVIDUAL STRING, THE APPLICATION OF DIGITAL PRESSURE TO ANY PARTICULARSTRING AT A REGION ABOVE A FRET BRINGING THAT STRING INTO ENGAGEMENTWITH THE ASSOCIATED INSERT ON THAT FRET, MEANS FOR ELECTRICALLYINSULATING SAID STRINGS FROM ONE ANOTHER, ELECTRICALLY CONNECTING MEANSCONNECTED WITH EACH OF SAID STRINGS AND ELECTRICAL CONNECTING MEANSEXTENDING THROUGH THE FRETS AND CONNECTED WITH EACH OF SAIDSTRING-ENGAGING INSERTS, SAID STRINGS AND SAID STRINGENGAGING INSERTSSERVING AS SWITCHING MEANS FOR CONTROLLING THE OPERATION OF AT LEAST ONEOTHER SOUND-PRODUCING DEVICE.